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Codex Leicester - A collection of scientific observations by Leonardo da Vinci, the Codex Leicester was written in the early 1500s. The 72-page manuscript is named after Thomas Coke, later the Earl of Leicester, who purchased it in 1719.

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Codex Leicester - Only one copy of Codex Leicester exists. The historic notebook is currently in the hands of Bill Gates, who paid over US$30 million in 1994 (equivalent to US$50 million in 2018) for the privilege of owning such a rare document.

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Mr. William Shakespeare's Comedies, Histories, & Tragedies - This first authoritative collection of Shakespeare's plays was published in 1623, seven years after the dramatist's death.

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Mr. William Shakespeare's Comedies, Histories, & Tragedies - The calf-bound book is often referred to by scholars as the First Folio. Around 750 copies were printed, and an example today would be easily worth US$4-5 million.

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The Declaration of Independence - Not a book, but a statement of immeasurable historic worth, the US Declaration of Independence is one of the rarest published documents in the world.

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The Declaration of Independence - Only 200 copies of it were printed on 4 July, 1776, and around 26 copies still survive.  An original is today valued upwards of US$9 million.

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'The Birds of America' - The French ornithologist John James Audubon (he later acquired American citizenship) produced 435 hand-colored life-size prints of a wide variety of birds in the United States.

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'The Birds of America' - The beautiful paintings were collected as a portfolio, 'The Birds of America,' and first published as a series between 1827 and 1838. Only about 200 complete sets were published, one of which fetched around US$8 million at auction in 2010.

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The Gutenberg Bible - Printed circa 1455, the Gutenberg Bible is the first mass produced printed work. (Photo: Wikimedia/CC BY-SA 2.0)

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The Gutenberg Bible - Iconic in status, only 48 copies of this exquisitely produced book survive, and just 31 are perfect. In 2007 a single leaf of one went on sale for US$74,000—a complete volume would be worth tens of millions of dollars.

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Ptolemy’s Geographia Cosmographia - While the maps are widely inaccurate, because his measurements were in error, Ptolemy demonstrates the use of a coordinate system based on the spherical nature of the Earth—hugely advanced geographical principles for the time. A copy of the Bologna edition of Ptolemy sold for around US$3 million in 2006.

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Ptolemy’s 'Geographia' (or 'Cosmographia') - Ptolemy, who lived around 100 CE, hand drew a manual of maps that had a profound influence on cartographers. In it, Ptolemy states that the world is spherical, and portrayed the world as he knew it at the time.

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King James Bible - Pictured is the first edition of the 'Authorized Version' of the English Bible, printed in London in 1611 by Robert Barker. Commissioned by King James I, it is also known as the King James Version.

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King James Bible - Copies in good condition are extremely rare, and a complete 1611 first edition would today be worth upwards of US$630,000.

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'Don Quixote' - 'The Ingenious Nobleman Sir Quixote of La Mancha,' to give the book its full title, was written by Miguel de Cervantes and published in 1605. (Photo: Wikimedia/CC BY-SA 4.0)

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'Don Quixote' - A founding work of modern Western literature, first editions of this masterful satire can fetch a tidy sum. Indeed, the last complete edition changed hands in 1989 for US$1.5 million. 

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'Tamerlane and Other Poems' - Edgar Allan Poe's first collection of poems was published anonymously in 1827—at the time the American writer wasn't at all sure of his worth as an author.

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'Tamerlane and Other Poems' - Only 50 copies were printed, and the collection received no critical attention. Collector's today are interested in the value of Poe's anonymity, plus the fact the work has since been recognized as one of the rarest first editions in American literature.

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'The Tales of Beedle the Bard' - Harry Potter fans will recognize The Tales of Beedle the Bard as that of the fictional book bequeathed by Albus Dumbledore to Hermione in the final Harry Potter book.

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'The Tales of Beedle the Bard' - The fictional book became such a hit that author J.K. Rowling illustrated and published seven handmade copies before officially releasing the title as a book of children's stories. One of the original limited so-called 'Moonstone' editions sold at auction in 2007 for US$3 million to benefit the Children's Voice charity. Magic!

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'On the Revolutions of the Heavenly Spheres' - Only 260 first edition copies of Nicolaus Copernicus' seminal work on heliocentric theory are known to exist. First published in 1543, the work contained the realization of a heliocentric universe, one where the Sun, not the Earth, is the center of our solar system.

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'On the Revolutions of the Heavenly Spheres' - His radical thesis offered an alternative model of the universe to Ptolemy's geocentric system, which had been widely accepted since ancient times. A first edition is worth anywhere between US$2-3 million.

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The Columbus Letter - This small four-page pamphlet is the first known document announcing the discovery of the New World. Reproduced from Columbus's own hand, only one copy survives from the original 1493 Barcelona print run.

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The Columbus Letter - Quickly reprinted in Rome, original second editions can still fetch US$600,000. 

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'Frankenstein; or, The Modern Prometheus' - The first edition (pictured) of Mary Shelley's masterpiece of Gothic horror was published anonymously in London in 1818.

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'Frankenstein; or, The Modern Prometheus' - Her name appeared on the second edition, published in 1823. Shelley's draft (pictured) describes her "man completed." Copies of the rare first edition can easily reach six-figure sums.

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'An Inquiry into the Nature and Causes of the Wealth of Nations' - Modern economic thought and the world's first collected descriptions of what builds nations' wealth formed the basis of Scottish economist and moral philosopher Adam Smith's magnum opus.

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'An Inquiry into the Nature and Causes of the Wealth of Nations' - Touching upon such broad topics as the division of labor, productivity, and free markets, a first edition of Smith's fundamental work is worth nearly US$130,000.

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'Wuthering Heights' - First published in 1847 under the pseudonym Ellis Bell, 'Wuthering Heights' is Emily Brontë's only novel.

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'Wuthering Heights' - Only 250 copies were originally printed, and a first edition of this classic of English literature can generate upwards of US$250,000 at auction.

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